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The lacrimal sac or lachrymal sac [1] is the upper dilated end of the nasolacrimal duct, [2] and is lodged in a deep groove formed by the lacrimal bone and frontal process of the maxilla. It connects the lacrimal canaliculi, which drain tears from the eye's surface, and the nasolacrimal duct, which conveys this fluid into the nasal cavity. [3]
The canal containing the duct is called the nasolacrimal canal.It is formed by indentations in the inferior nasal conchae, maxilla and lacrimal bone.The canal drains into the nasal cavity through the anterior portion of the inferior meatus, which is between the inferior concha and the floor of the nasal cavity.
Specifically, the lacrimal bones help form the nasolacrimal canal necessary for tear translocation. A depression on the anterior inferior portion of one bone, the lacrimal fossa, houses the membranous lacrimal sac. Tears, from the lacrimal glands, collect in this sac during excessive lacrimation.
Involutional stenosis is probably the most common cause of nasolacrimal duct obstruction in older people. It affects women twice as frequently as men. Although the inciting event in this process is unknown, clinicopathologic study suggests that compression of the lumen of the nasolacrimal duct is caused by inflammatory infiltrates and edema.
The lacrimal apparatus is the physiological system containing the orbital structures for tear production and drainage. [1]It consists of: The lacrimal gland, which secretes the tears, and its excretory ducts, which convey the fluid to the surface of the eye; it is a j-shaped serous gland located in lacrimal fossa.
Excessive moisture as tears collected in the lacrimal sac travel down the nasolacrimal ducts where they drain into the inferior meatus in the nasal cavity. [23] Most of the nasal cavity and paranasal sinuses is lined with respiratory epithelium as nasal mucosa. In the roof of each cavity is an area of specialised olfactory epithelium.
The anterior attachment of the medial palpebral ligament is to the frontal process of the maxilla in front of the lacrimal groove (near the nasal bone and the frontal bone), [1] and its posterior attachment is the lacrimal bone. Crossing the lacrimal sac, it divides into two parts, upper and lower, each attached to the medial end of the ...
There is a single lacrimal canaliculus in each eyelid, a superior lacrimal canaliculus in the upper eyelid and an inferior lacrimal canaliculus in the lower eyelid. The canaliculi travel vertically and then turn medially to travel towards the lacrimal sac. At the bend, the canaliculus is dilated and called the ampulla.